Tumor-Stroma Ratio in Basaloid and Conventional Laryngeal Squamous Cell Carcinoma: Prognostic Significance and Concordance in Paired Biopsies and Surgical Samples

Abstract

Basaloid squamous cell carcinoma (BSCC) is a subtype of squamous cell carcinoma (SCC) associated with a poor prognosis. Tumor–stroma ratio (TSR) has been introduced as a prognostic feature in many solid tumors. TSR was investigated in a series of laryngeal BSCCs and compared with a group of stage-matched conventional SCCs (cSCCs), in both preoperative and surgical specimens, with the intent of ascertaining the more aggressive behavior of BSCC and verifying the presence of stromal-related causes. A series of 14 consecutive laryngeal BSCCs and a control group of 28 stage-matched conventional cSCCs were analyzed. A higher nodal metastasis presence was found in BSCCs (57.1% vs. 28.6%). The recurrence rate was 33.5% and 63.6% in the cSCC and BSCC groups; disease-free survival (DFS) was higher, though not significantly, in patients with cSCC. TSR, large cell nests, and tumor budding showed a moderate to very good agreement, and stroma type a good to very good agreement between biopsies and surgical specimens in the cSCC group. In the BSCC group, agreement was poor to very good for TSR and stroma type, and good to very good for large cell nests and tumor budding. Age was the only feature significant in predicting recurrence in the BSCC group (p = 0.0235). In cSCC, TSR low/stroma rich cases, when evaluated on biopsies or surgical specimens, were associated with lower DFS (p = 0.0036; p = 0.0041, respectively). Laryngeal BSCCs showed a lower DFS than cSCCs, even if statistical significance was not reached. TSR, evaluated in laryngeal biopsies and excised tumors, was prognostic in terms of DFS in cSCC but not in BSCC cases.

Tumor-stroma ratio can reliably be assessed in pre-treatment biopsies, shows substantial agreement with resections, and is significantly associated with overall and recurrence-free survival in early-stage oral squamous cell carcinomas

“…Only very few studies compared tumor-stroma ratios in resection specimens and matching biopsies in head and neck tumors. For laryngeal carcinomas, good agreement could be demonstrated for stromal content and cell nest size in two independent cohorts [12,13]. as of yet, these data have not been published for OSCC.…”

Prognostic Significance of Tumor-associated Stroma in Nasopharyngeal Carcinoma

“…8,22,25 Furthermore, TSR provides prognostic information based on the stromal compartment of tumors, complementing tumor cell-related prognostic information. Interestingly, in recent studies of head and neck cancers including laryngeal squamous cell carcinoma 15,26 and oral tongue squamous cell carcinoma 27 the visual estimation of TSR has shown concordance between tissue biopsies and surgical samples. A similar concordance has been reported in esophageal adenocarcinoma 28 and invasive breast cancer.…”